Bacteria of the Roseobacter clade of marine alpha-Proteobacteria stand out as some of the most critical players in the oceanic sulfur cycle due to the ability of several genera to degrade dimethylsulfoniopropionate (DMSP). While roseobacters are wide-spread throughout the marine ecosystem, their abundance is significantly correlated with DMSP-producing algae, especially prymnesiophytes and dinoflagellates, such as Prorocentrum, Alexandrium and Pfiesteria species.
Roseobacters have abundant and diverse transporters, complex regulatory systems, multiple pathways for acquiring carbon and energy in seawater, and the potential to produce secondary, biologically active metabolites.